Apparatus for withdrawing liquids from closed containers



F. J. HARLow. 2;2815,710

Filed June 2v, 193e INV EN TOR; FREDERICK J. HARLOW BY M, h ATTO S.

June 9, 1942.

APPARATUS FOR yWI'I'HIRAWING LIQUIDS FROM CLOSED CONTAINERS PatentedJune 9, 1942 Frederick J. Harlow, Bartlesville, Okla., assigner toPhillips Petroleum Company, a corporation of Delaware Application .lune27, 1938, Serial No. -216,148

(C1. sz-1)' "I Claim.

This invention relates to apparatus -for unloading liquids from closedvessels andin its more specific aspects, to apparatus for pumpingvolatile liquids from vessels by means of a pump submerged in theliquid.

Heretofore, considerable difculty has been experienced with conventionaltypes of pumps placed outside the main vessel or container when pumpingliqueed petroleum gas, such as butane, propane or' mixtures thereof. Theprincipal trouble has been c iue to the fact that the usual pumpingmethods and apparatus often resulted yin gas lock due to expansion ofthe volatile liquids. This gas lock causes pumping to cease and thebearings to become dry and overheated. In addition to objectionable,interruptions in operations, the pumps frequently 'become either par-`tially or completely destroyed. In a pump and driving Amechanismconstructed in accordance with the present invention, various types ofliquids including liquefied petroleum gas, gasoline, oils, varnishes,paints, and even tar, may be readily and efficiently pumped from closedcontainers. It will be merely a matter of mechanical skill to alter thedesign of this equipment in' order to use it eiectively with liquids ofdiffer- ,ent specic gravity, volatility, and viscosity.

The primary object of this invention is to provide apparatus whicheliminates all possibility of gas lock in the pump when pumping volatileliquds'out of vessels such 'as tank cars.

Another object of this invention is to equip tank cars for transportinghighly volatile liquids with individual pumps'which are adaptable tobeing actuated by a single source of power at unloading points. In thismanner, the cost of the equipment for withdrawing the liquids ismateriallyvreduced as onemotor may be used to evacuate a group of carsin succession.

A further object of this invention is to provide apparatus fordischarging the liquid contents of a container by means of a pump whichis submerged in the liquid. By placing the pump in direct contact withthe liquid, greater efllciency of operation vis obtained; and,furthermore, higher pumping capacities may be maintained. Whereliquefied petroleumgas is being pumped,

the pressure in the container tends to assist the provide apparatus fordischarging liquids from containers, which apparatus is reasonable inrst cost, inexpensive to operate and maintain,

and thoroughly dependable toperform its intended functions. The aboveand additional objects and advantages will be apparent from thefollowing description and annexed` drawing which respectively describe,and illustrate preferred embodiments of. my invention: and wherein:

Figure 1 is a vertical cross sectional view o 'I portions of a tank carwith the apparatus comprising the present invention mountedv thereon.Figure 2is an elevation view of another embodiment of my invention.

Referring to the drawing and more particularly to Figure 1, thereofReference numerals I0 and Il indicate the upper and lower portions,respectively, of a cony tainer for liquefied petroleum gas, suchvas a'railway tank car.

Generally, containers and tank cars of thistype are provided withcoverings of cork or other suitable insulating materiall2 to control thetemperature of the contents'thereof. At the top ofthe caris en openinginthe formof a collar I3having an annular flanged ring Il. A closure I5is removably connected to ring Il by a series of bolts i6. A domeY I1 issupported on closure lIii land. attached thereto by bolts i8.

The dome is provided with a cover I9 which isl pivotally mounted to thedome at 20.

A vertical shaft centrifugal pump is represented b'y pump rotors 2i,drive shaft 22,V and tubular shaft housing 23. While it is apparent thatvarious types of vertical shaft pumps may be employed advantageously forthe purposes of this invention, I prefer to use a multi-stagecentrifugal pump of the type illustrated. It is observed that the lowerportion of the pump extends into a sump 24 in the bottom of the tank carand is braced thereto by straps or brackets 25 which eliminateundesirable vibrations of the pump while the car is in transit or duringpumping operations. The shaft housing 23 is connected to closure I5 by acollar 28. A connector 29, concentric with lthe drive shaft andcontaining suitable frictionless bearings, -is located in closure l5.This connector supports saidv drive shaft and is attached to the closureby a series of stud bolts 30.- A packinggland 3i, also con,- centricwith the drive shaft and positioned 'ad-v jacent the connector is usedto prevent leakage. 'I'he upper end portion of the drive shaft issplined as indicated at32. l

A plurality of withdrawal-'conduits 33 arein communication with theinterior of housing 23, pass through closure I5 and terminate in T--unions 3l. Each'T-union is provided with an excess flow check valve 35and a plug 36.v 'In The motive power for actuating the pump is safetyshould be of an explosion proof type. A chain 4|, connected to the motorby an eye bolt 42 is utilized to mount or remove they motor with respectto the pump. Two legs 43 of a tripod support are shown inthe drawing.lThe upperl end of each leg is pivoted to the motor at 44 while the lowerportion 45 of each leg is forked to iit over the edge of the dome.Through the agency of set screws 45, the tripod legs 43 are rigidlymaintained in position on the car dome. The motor drive shaft 41 isequipped with a universal joint and terminates at its lower extremity ina splined socket 49 which engages splined shaft 32 of the pump.

The practice of this embodiment of my invention contemplates equippingtank cars for the transportation of liquefied petroleum gas withindividual pumps. 'I'he pump, including drive shaft 22, housing 23, pumprotors 2|, and discharge conduits 33, is supported by closure |'5 andinstalled as a unit in the cars. Neither the closure -supplied by amotor 4l. which in the interests of r agendo `/tom of the tank car, thehighlyfobjectionablepossibility of gas lock in the pump experiencedheretofore is completely eliminated. Pumping continues until the tank issubstantially empty, at which time the motor is stopped; valves 35 areclosed; the discharge hose is disconnected and plugs 35 are reinsertedin the T-unions; stud bolts 46 are loosened; and the motor is raisedupwardly and swung away from vthe car. The dome cover is then replacedand we are ready to proceed with the evacuation of another car.'

' of having a separate pump in each container or tank car, I propose touse butone pump and one 'motor at the storageplant or car terminus forthe purpose of withdrawing the contents of the nor the pump is removedfrom the cars except been lled with liqueiied petroleum gas, on reachingtheir destination, are run to a siding and stopped at an unloading pointwhere the contents of the cars are to be withdrawn. At the unloadingspot, a single motor 40 is utilized to successively empty each car.Individual tank car dome covers I3 are first opened and the motor,through the agency of chain 4I and eye bolt 42, is readily swung overthe dome by any conventional means such as a crane. The motor is thenlowered to operatingl position so that forked ends of legs 43 of themotor tripod t on the edge of the dome and are fastened thereto by setscrews 46. At the same time splined socket 43 is placed in engagementwith splined portion 32 of pump shaft Plates 38 are now moved away fromopenings 31 in the car dome and plugs 36 are removed from T-unions 34.Discharge hose is inserted through openings 31 and connected to theT-unions in place of the plugs. With valves 35 set to any desired degreeof opening, the motor isplaced inof the car through the discharge hose.It is notedv that the pressure of the vapor in the upper portion of thetank car serves to aid the pump and thereby increases its eillciency andoutput. Vilince the pump rotors are located in sump 24 in the botcar.The end portion of a tank car is indicated by reference numeral 50. Ailexible conduit 5| is connected to the car by means of a coupling 52.This-conduit also communicates with the interior of chamber orreceptacle 53 in which is mounted a pump of the type described above.The liquid is introduced by conduit 5| into chamber 53 where it istransmitted by the pump into discharge conduit 54. Asv in' the case ofthe first described embodiment of the present invention,

the pump rotors 2| are submerged below the liq-m uid level in thechamber in order' to prevent gas lock. Any vapors that may form inlchamber 53 pass through gas conduit 55, coupling 56, and back to thetank car.

It is to be understood that the form of this invention, herewith shownand described, islto be taken as a preferred example of the same andthat various changes in size, shape and arrangement of parts may beresorted to without departing from the spirit of this invention, andfurther that the theories of operation set out, although believed to beaccurate, are not to be considered as the sole basis of theoperativeness of this device, but that this device does operatesuccessfully whether or not upon the principles described herein, thisinvention to be limited only by the appended claim.

I claim: Y

In apparatus for withdrawing a volatile liquid from a closed container,the combination comprising a closed receptacle; a conduit for placingthe lower portion of the receptacle in communication with the lowerportion of the container; a conduit for placing the upper portion of thereceptacle in communication with the upper portion of the container;pumping means in the receptacle, saidpumping means including a pump, adrive shaft operable from the exterior of the receptacle, a housingconcentric with the drive shaft, and discharge conduit communicatingwith the housing and the exterior of the receptacle; and means externalthe receptacle for operating th pumping means.

FREDERICK J. HARLOW.

